/**
 * Copyright 2009 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * 	http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.xume.solrj.criteria.criterion;

import java.util.Iterator;
import java.util.List;

/**
 * @author Johan Siebens
 */
public abstract class AbstractJunction implements Criterion {

	private List<Criterion> criterions;

	private String operator;

	public AbstractJunction(String operator, List<Criterion> criterions) {
		this.criterions = criterions;
		this.operator = operator;
	}

	public String toQueryFragment() {
		if (criterions == null || criterions.isEmpty()) {
			return "";
		} else if (criterions.size() == 1) {
			return criterions.get(0).toQueryFragment();
		} else {
			StringBuilder fragment = new StringBuilder("(");

			for (Iterator<Criterion> iterator = criterions.iterator(); iterator.hasNext();) {
				Criterion criterion = iterator.next();
				fragment.append(criterion.toQueryFragment());

				if (iterator.hasNext()) {
					fragment.append(" " + operator + " ");
				}
			}

			fragment.append(")");

			return fragment.toString();
		}
	}

}
